1. Field of the Invention
The present disclosure relates to a vacuum cleaner. More particularly, the present disclosure relates to a cyclone dust-separating apparatus of a vacuum cleaner, which draws in external air and then separates dust or dirt therefrom.
2. Description of the Related Art
In general, a cyclone dust-separating apparatus provided in a vacuum cleaner is an apparatus, which whirls air laden with dirt or dust and separates the dirt or dust therefrom. Such a cyclone dust-separating apparatus has been recently widely used because it can be semi-permanently used without any inconvenience of having to frequently replace dust bags.
As disclosed in U.S. Pat. No. 6,350,292, a cyclone dust-separating apparatus usually has a cyclone unit vertically and elongately installed, a cyclone body with an air inflow part and an air discharging part formed at a side and a top thereof, respectively, and a dust collecting unit connected to a bottom part of the cyclone unit. Accordingly, external air is drawn in through the side of the cyclone body and lowered while being swirled therein, and dirt or dust removed from the air is collected in the collecting unit. However, such a conventional cyclone dust-separating apparatus requires forming the dust collecting unit in a relatively small size because the cyclone unit has large height. As a result, the conventional cyclone dust-separating apparatus is inconvenient to use, in that the dirt or dust collected in the dust collecting unit should be frequently emptied.
To address the problem as described above, in recent, a cyclone dust-separating apparatus in which a cyclone body is horizontally installed to allow a dust collecting unit to have a larger height or size is actively being developed. Such a cyclone dust-separating apparatus is advantageous in that since it can enlarge a volume of the dust collecting unit, it addresses the problem that dirt or dust collected in the dust collecting unit should be frequently emptied. However, in the cyclone dust-separating apparatus, there is a problem that since the cyclone body is formed in a cylinder shape, the diameter of which is uniform in a longitudinal direction thereof, air increases its flowing speed when it is discharged through an air discharging part of the cyclone body after flowing into the cyclone body. Such an increase in the flowing speed of the air at the air discharging part not only increases a pressure loss, but also an operating noise. The increase in the pressure loss may increase an output of a suction motor of the vacuum cleaner, which is required to obtain the same dust-separating efficiency, thereby causing the vacuum cleaner to use more power.